The present invention relates to a scroll compressor.
Generally, a scroll compressor includes a fixed scroll, which is fixed to a housing, and a movable scroll, which orbits with respect to the fixed scroll. The fixed scroll includes a fixed base plate and a fixed spiral wall projecting from the fixed base plate. The movable scroll includes a movable base plate and a movable spiral wall projecting from the movable base plate. The fixed spiral wall and the movable spiral wall are engaged with each other to define a compression chamber. The orbital movement of the movable scroll decreases the volume of the compression chamber and compresses refrigerant. Japanese Laid-Open Patent Publication No. 2010-14108 describes an example of such a scroll compressor.
In the scroll compressor, a large centrifugal force acts on the movable scroll especially when the rotation shaft rotates at a high speed. This increases the noise generated when the movable spiral comes into contact with the fixed spiral wall. When the movable spiral wall is spaced apart from the fixed spiral wall to avoid contact between the spiral walls, leakage of the refrigerant from the compression chamber increases when the rotation shaft rotates at a low speed. This lowers the compression performance.